AIC 521132.02 – CommandQuad™ Range Switch C Circuit Conflict. John Deere AIC System Alert.

AIC 521132.02 (AIC )

Code: 521132.02



This error code, AIC 521132.02, is triggered by a malfunction within the CommandQuad™ transmission range switch C, where the ON and OFF contacts are registering the same value simultaneously. This anomaly suggests a failure in the switch’s mechanism or an electrical issue within its circuit, leading to incorrect or ambiguous gear selection signals.


To mitigate potential risks associated with incorrect gear engagement, the control unit has automatically placed the vehicle in a recoverable PARK position.


  • Conduct a detailed examination of range switch C for any physical damage or mechanical failure that might cause the contacts to malfunction. Look for signs of wear, debris, or corrosion that could impact the switch’s ability to differentiate between ON and OFF states.
  • Utilize diagnostic tools to test the electrical functionality of the switch. Ensure that each contact is independently activating and deactivating as required.
  • Check the wiring and connectors for the range switch C circuit for any signs of damage, loose connections, or shorts that might be causing the contacts to cross-signal.
  • Replace the faulty switch or repair any identified issues with the circuit. Make sure all repairs adhere to the manufacturer’s specifications and that the new or repaired switch is correctly integrated into the system.
  • After the necessary repairs are completed, recalibrate the transmission settings associated with range switch C and test the system extensively to ensure that the PARK condition can be exited safely and that the switch operates correctly across all intended functions.


Regular maintenance and timely resolution of switch and circuit conflicts in transmission systems are crucial for the safe and effective operation of heavy machinery. Continuous monitoring and proactive management of these components help maintain system reliability and prevent potential failures that could lead to more significant problems.